Mimulus ringens is a species of monkeyflower known by the common names Allegheny monkeyflower and square-stemmed monkeyflower. It is native to eastern and central North America, and there are occurrences in the western United States, some of which may represent introductions. It grows in a wide variety of wet habitat types. This is rhizomatous perennial growing 20 centimeters to well over a meter tall, its 4-angled stem usually erect.